“Body in white” (BIW) refers to the stage in an automobile's manufacturing where the majority of the metallic components of the automobile are welded together, before adding other subsequent parts and sub-assemblies. The structure connecting the body side of a vehicle to its lower back joints is extremely critical for maintaining the overall torsional stiffness of the body in white structure. Many conventional mechanisms and structures have been deployed for increasing the rigidity (stiffness) and load transferring virtue of the body side structure. These structures are typically disposed between the lower portion of a specific side-pillar of the vehicle and the corresponding underbody structure underneath, mainly due to certain limitations in the assembly process. However, a major problem in the currently deployed structures/mechanism is their low effectiveness in transferring loads and maintaining rigidity between the lower portion of the side pillars, to the underbody structure. Further, unibody vehicles generally use body panels and a floor pan that contributes to their structure, and their main body structure is fairly stable, as their center of gravity lies within the lower portion of the vehicle. Specifically, the underbody structure in many unibody vehicles has more strength compared to the upper portions, and hence, an effective strain energy transfer towards the underbody structure in such vehicles is an extremely critical aspect for maintaining side structure's stiffness and stability.
In many vehicles, certain hollow tubular members are welded to the side frame of the vehicle to increase the strength of the side structure. In one such example, two hollow tubular members are mounted on the side frame of the vehicle that receives the door, and the members are joined together by a non-tubular reinforcement member. The reinforcement member takes the stress away from the curved corners of the side frame, and prevents the concentration of stress at the joints. However, the mechanism is not efficient in reinforcing the side structure, and in transferring loads and developing adequate stiffness between the side pillar & underbody members.
Considering these problems, there is a need for an effective and efficient mechanism for reinforcing the side structure of a vehicle, and for increasing load transfer & stiffness between the side frame to the underbody structure of the vehicle.